External hard drive volume disappeared

[eranbeard]

My set up as background:

Macbook Pro (late 2015 13" top spec) with latest OS
Connected to Thunderbolt display
2 external WD My Passport hard drives connected to display
I use 'Mountain app' to dismount the drives before unplugging

Up until yesterday I used one of the My Passports as my main images hard drive. I'd partitioned it into 2 sections, with 1 assigned to the Time Machine and the other my images folder.

My MBP crashed overnight, and when I restarted, I found that the volume containing the image folder had vanished. I checked Disk Utility, and used Disk Drill too, but they can't even see the previous volume on the drive - it's not greyed out, it just doesn't appear at all.

The drive itself appears now as 'Time Machine', and functions fine as the Time Machine.

I'm not sure what to do since the drive functions fine, but there's no evidence that any of my other image files were ever there.

I've tried with another Macbook and it didn't appear there either.

Does anyone have any advice on how to further troubleshoot?

After running a List All Drives in the Terminal'BACKUP BLACK' is a separate drive unrelated to this issue.)

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_APFS Container disk1 1.0 TB disk0s2


/dev/disk1 (synthesized):

#: TYPE NAME SIZE IDENTIFIER

0: APFS Container Scheme - +1.0 TB disk1

Physical Store disk0s2

1: APFS Volume Macintosh HD 431.0 GB disk1s1

2: APFS Volume Preboot 19.6 MB disk1s2

3: APFS Volume Recovery 509.8 MB disk1s3

4: APFS Volume VM 5.4 GB disk1s4


/dev/disk2 (external, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *4.0 TB disk2

1: EFI 209.7 MB disk2s1

2: Apple_HFS BACKUP (Black) 4.0 TB disk2s2


/dev/disk3 (external, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *2.0 TB disk3

1: EFI EFI 209.7 MB disk3s1

2: Apple_HFS Time Machine 2.0 TB disk3s2

 

[Fishrrman]

"Does anyone have any advice on how to further troubleshoot?"

My suggestions:

Power down the MacBook -- all the way off.

Next, DISCONNECT EVERYTHING from the MacBook Pro, INCLUDING THE EXTERNAL DISPLAY.
Hubs, too.
EVERYTHING.

Connect the drive that won't mount.
Now, press the power-on button.
Can you get to the finder?
If so, just..... wait a while.

Let it "sit this way" for about 30 minutes.
Does anything change?

WHY I asked you to do this:
Sometimes, with a drive that has corrupted drivers, the finder will try to repair the drive on its own. But it can take some time.

No promises that this will work, it's iffy at best.
But doesn't hurt to try.

Final thoughts:
You said the problem drive was just used for "images" (whatever that means) and time machine?
In other words, there is no "primary data" on it? (by "primary" data, I mean data that doesn't exist anywhere else).
If that's the case, I would just ERASE the drive, run Disk Utility's "repair disk" function on it about 5 times in succession, and if I received "a good report" each time, I'd just use it again.

I -WOULD NOT- initialize the drive to APFS. For a platter-based drive, stick with HFS+ (Mac OS extended with journaling enabled, GUID partition format).